I've been using an adapter with my digital SLR cameras for a long time -- to allow the use of my many manual-focusing lenses.
The adapter has glass in it to allow for infinity focus, and I haven't had any problems with it. It does magnify the focal length of the lens by 1.25X, however, so a 50mm lens becomes a 62.5mm lens.
I keep running across comments (not just on this Forum) that "POO-POO" adapters with glass as "degrading the image", and so forth. So I decided to run some simple tests on my gear. Like I said, I've never had a problem.
I realize that there are many different adapters and their optics won't be the same, but I'm only interested in my adapter -- an inexpensive Spiratone adapter to put Minolta-mount MF lenses on my Sony full-frame a-mount AF cameras.
Adapters may vary in quality. The same is true with lenses. I realize that my tests are comparing the results from different lenses -- one AF, the other MF. For example, I might be comparing a Sigma AF 24mm lens to a Vivitar MF 19mm lens (with adapter producing a 24mm optic).
I took pictures at f8, with the camera on a tripod using mirror lock-up and a cable release -- of high quality resolution charts at high magnification (cropping), and viewed them "unlabe;led". In other words, even though I took the pictures, I did know which was which.
In all of my comparisons, I could not pick out any of the images as better than the other -- sharper, clearer, better, etc.
So I'm convinced that using my MF-to-AF "Glassy" adapter has no quality limitation with my MF lenses -- other than the increase in focal length, lack of an auto-diaphragm, and lack of AF. None of those are big problems for me.
I realize that results may be different with the aperture wide open -- as with any tele-converter -- but normally, I try to set my aperture as close to f8 as possible.
If you've shied away from adapters with glass due to other people comments, you may want to reconsider -- and run some simple tests. Sure, there will be some limitations, but they may or may not be significant to you. You might be pleasantly surprised -- like me!
The adapter has glass in it to allow for infinity focus, and I haven't had any problems with it. It does magnify the focal length of the lens by 1.25X, however, so a 50mm lens becomes a 62.5mm lens.
I keep running across comments (not just on this Forum) that "POO-POO" adapters with glass as "degrading the image", and so forth. So I decided to run some simple tests on my gear. Like I said, I've never had a problem.
I realize that there are many different adapters and their optics won't be the same, but I'm only interested in my adapter -- an inexpensive Spiratone adapter to put Minolta-mount MF lenses on my Sony full-frame a-mount AF cameras.
Adapters may vary in quality. The same is true with lenses. I realize that my tests are comparing the results from different lenses -- one AF, the other MF. For example, I might be comparing a Sigma AF 24mm lens to a Vivitar MF 19mm lens (with adapter producing a 24mm optic).
I took pictures at f8, with the camera on a tripod using mirror lock-up and a cable release -- of high quality resolution charts at high magnification (cropping), and viewed them "unlabe;led". In other words, even though I took the pictures, I did know which was which.
In all of my comparisons, I could not pick out any of the images as better than the other -- sharper, clearer, better, etc.
So I'm convinced that using my MF-to-AF "Glassy" adapter has no quality limitation with my MF lenses -- other than the increase in focal length, lack of an auto-diaphragm, and lack of AF. None of those are big problems for me.
I realize that results may be different with the aperture wide open -- as with any tele-converter -- but normally, I try to set my aperture as close to f8 as possible.
If you've shied away from adapters with glass due to other people comments, you may want to reconsider -- and run some simple tests. Sure, there will be some limitations, but they may or may not be significant to you. You might be pleasantly surprised -- like me!
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